Speakers and Transducers - Haptic Devices for Augmentation, Entertainment, and Wellness

Expanding on previous articles about bass shakers and motion platforms, this article from Mike Klasco (Menlo Scientific) looks at exciting evolutions in haptic transducers and actuators that are being used in a growing number of applications - all of which depend upon audio sources for input. The ability to interact with the world through vibration and touch is central to all of our lives, and now increasingly so. This article was originally published in audioXpress, February 2022.

In this article, James Croft reviews a generic “Loudspeaker” concept patent, granted to Teppei Yamada, of Tokyo, Japan, on behalf of Zorzo Co., Ltd. and which describes a somewhat surprising concept of a loudspeaker that includes a hermetically sealed enclosure, with a driver outside of an enclosure and a second driver inside, with a pipe communicating between the two drivers. The second driver is configured to output a signal of opposite phase to that of the first driver. This article was originally published in Voice Coil, October 2016.

As the audio industry gradually resumed its trade show calendar in result of the global pandemic, Oliver A. Masciarotte offers a report from the 2022 edition of Audio Expo North America, better known as AXPONA - the most important annual hi-fi and high-end audio show in the US. As audio enthusiasts and audiophiles returned once again to listening in person at the Renaissance Schaumburg Convention Center Hotel, there was a lot to explore in very little time. This article was originally published in audioXpress, July 2022.

In this article, James Croft looks at a patent awarded to David Russell (Toronto, CA); and John French (Caledon, East, CA) on behalf of Audera Acoustics, Inc., Schomberg CA. The patent describes a generic acoustic high displacement transducer system, containing a diaphragm position sensing module, a controller with a transmitter, so that the voice coil moves at least partially in response to the control signal.

This article reviews a patent originally granted to inventors Philip R. Clements; (Tempe, AZ), Boaz Shalev; (Needham, MA), and James Joseph Croft, III; (Bellevue, WA), which has now expired. The patent describes a low-frequency transducer system with a multi-compression chamber, where an inverse horn structure is employed in combination with a resonance-distortion filter chamber. This was the third patent granted on Atlantic Technology’s low frequency system known by the trademark name H-PAS (High Pressure Acceleration System). This article was originally published in Voice Coil, September 2016.

Exploring some pressing topics in headphone technology, in this article Hans W. Gierlich addresses the requirements for effective performance testing of communication headsets that use active noise cancellation (ANC) technologies, test setups, testing equipment, and setup conditions needed to correctly assess ANC performance. From the right choice of artificial ears and the latest ITU-T recommendations in that domain, to ANC performance measurements and talk-though performance. This article was originally published in audioXpress, June 2022.

This important article revisits the evolution of Rub & Buzz measurements in loudspeakers, headphone drivers, and microspeakers production lines, and how these are being addressed using the next-generation of perceptual algorithms. Steve Temme offers a valuable comparison with what can be accessed today using modern methods, and what to apply to access production faults, determine thresholds for production yields, or understand the real impact on consumer's perception. This article was originally published in audioXpress, April 2022.

This review looks at an independently patent submitted in 2013 and awarded in 2016 to Jack Nilsson (Canton, OH), describing a system and method for an audio system including a first speaker that reproduces sounds in a first frequency range and a second speaker that reproduces sounds in second frequency range. As James Croft comments, the patent is interesting in its purposeful application of breaking currently established rules and may be useful in certain applications or environments. This article was originally published in Voice Coil, August 2016.

In this review of the GaN Systems amplifier evaluation kit, Stuart Yaniger shares his explorations of the features and benefits of GaN (gallium nitride) power semiconductors, and explains why the technology is not only enabling great sounding audio amplifiers but is also bound to completely disrupt the Class-D segment in high power ratings. This article was originally published in audioXpress, April 2022.

This article reviews a patent application submitted in 2010 by to two inventors, on behalf of Jazz Hipster Corp. (Taiwan), regarding an improved structure of a speaker using the surround to reduce the resistance of the diaphragm excursion, which helps to generate a more linear diaphragm movement, with less resistance, and reduced distortion. As James Croft noted, the approach had been used in the past, but its use decreased due to the high-performance achieved with well-designed roll-surrounds, at a lower cost. No surprisingly this patent was subsequently abandoned.